Avoid potential CSS selector conflict

[1j01]

The CSS uses some generic selectors like error and success that are likely to conflict.

Possible solutions:

• Prefix all selectors (currently some of them are prefixed with simple-console- and others are not)
• Make the library into a Web Component so styles can be scoped to the Shadow DOM

Scoping selectors to .simple-console * (as opposed to prefixing the classes) is not an option, at least for .dark and .light, which are user-applied classes which should work applying them outside of .simple-console; and those are also part of the API currently, whereas other selectors are not, so maybe they should stay unprefixed.